1. Field of the Invention
The present disclosure relates generally to computer graphics and animation and, more particularly, to techniques for deforming graphical objects.
2. Description of the Related Art
Deforming graphical models is an important operation in many areas of computer graphics. Deformation of planar curves is a basic operation in two-dimensional (2D) as well as three-dimensional (3D) graphics systems. Many significant industries, such as portions of the entertainment industry and the medical imaging industry, rely heavily on suites of computer graphics tools that include deforming operators. These operators may be included in a rendering engine configured to render a 2D image of a 2D or 3D model.
Objects are often deformed by manipulating a set of weighting fields that correspond to a set of feature specifications. Weighting fields modulate the influence of multiple source/target feature mappings on model points. The set of weighting fields is also defined over an undeformed model, and performs the function of determining the relative influence of a set of scaled transformations over elements in the undeformed model. Weighting fields define a region of influence. These weighting fields may be included in computing a deforming function.
Weighting fields may be modified using various techniques. One such technique may involve mouse cursor drags in screen space. For example, a user may drag a mouse such that drags to the left decrease the weight value, while drags to the right increase the weight value. Such a technique may not be without limitations. The user may have little idea as to the effect of a specified weight value on the deformation, and depending on the complexity of graphical objects, the update may take too long.
Accordingly, there remains a need in the art for an improved technique that minimizes the limitations of the prior art, as described above.